灰色系统理论在柽柳属植物扦插繁殖筛选中的应用

采用灰色系统关联度分析方法,分析并计算了8个柽柳属植物种之间的关联度以及它们扦插繁殖中的7个观测指标值间的关联度大小,结果表明:柽柳枝条扦插繁殖观测指标间的关联度大小顺序是茎粗>地上生物量>主根长>株高>侧根数>一级分枝数;柽柳种间的关联度大小顺序是中国柽柳>甘肃柽柳>甘蒙柽柳>刚毛柽柳>短穗柽柳>长穗柽柳>紫杆柽柳>多枝柽柳,关联度的大小可以反映出柽柳种间及扦插繁殖观测指标间的主次顺序。     

大数据运作平台下的植保机作业布局研究

为进一步提升无人植保机应用的合理性与高效性,以大数据运作平台技术为支撑,针对其作业布局展开研究。通过系统分析植保机作业过程与主要控制组件,根据田间飞行作业特点,确定系列核心控制参数,并依据大数据布局内部算法分配规则建立大数据运作模型。同时,考虑各系统模块的数据耦合性,生成大数据运作平台下的植保机作业布局并进行试验,结果表明:在各自占空比一定条件下,喷洒流量在0.3~0.6L/min波动时,所获取的流量误差控制在6.33%~15%;选取关键对比控制参数,较一般作业布局状态而言,基于大数据平台作业布局下的植保机续航能力可提升7.79%,试验效果良好。该布局优化充分提高了植保机的作业效率,可为类似农机系统布局提供改善思路。     

Soil bacterial characteristics between surface and subsurface soils along a precipitation gradient in the Alxa Desert,China

Bacteria in desert soil have unique phylogeny and important ecological functions, and theirresponses to changes in precipitation need further attention. However, relevant studies have mainlyfocused on the surface soil, and studies on the responses of bacteria at different soil depths to variationsin precipitation are rare. Thus, we used 16S rDNA high-throughput sequencing to investigate the changesin soil bacterial distribution along a mean annual precipitation gradient (50–150 mm) in the Alxa Desert,China, and compared the variation characteristics in the surface soil layer (0–10 cm) and subsurface soillayer (10–20 cm). Results showed that soil bacterial communities significantly changed along theprecipitation gradient in both soil layers. However, the subsurface soil layer could support bacterialcommunities with higher diversity and closer internal relationships but more internal competition than thesurface soil layer. Additionally, compared with the surface soil layer, variations in diversity andco-occurrence patterns in the subsurface soil layer were more in line with the changes in the mean annualprecipitation, while bacterial community structure was less variable in the subsurface soil layer. Comparedwith the mean annual precipitation, soil moisture had little influence on the structure and diversity of soilbacterial community but had a high correlation with intercommunity connectivity. Therefore, soilmoisture might play a complex role in mediating environmental conditions and soil bacterial communitycharacteristics. Due to the different responses of surface and subsurface soil bacteria to the changes inprecipitation, it is necessary to distinguish different soil layers when predicting the trends in desert soilbacterial conditions associated with precipitation, and prediction of subsurface soil bacteria may be moreaccurate.     

Root exudation of prometryn and its metabolites from Chinese celery (Apium graveolens)

Root exudates from Chinese celery (Apium graveolens) and Chinese cabbage (pak choi, Brassica chinensis) plants treated by prometryn, an herbicide, were qualitatively and quantitatively investigated and compared under hydroponic cultivation. Prometryn and its metabolites released into the nutrient solution were analyzed by ultra-performance liquid chromatograph coupled with orbitrap mass spectrometer to investigate whether this xylem-mobile herbicide is exuded from the roots. The results showed that celery and pak choi had different root exudation profiles. Celery metabolized prometryn to prometryn sulfoxide and released both compounds from the roots. In contrast, pak choi barely metabolized or actively released prometryn from the roots. The concentration of prometryn sulfoxide released from celery after 96 hr was 21 µg/L, which was nearly one-third that of released prometryn. Our results indicate that the root exudation and translocation of xylem-mobile herbicides could be significant in plants and are highly species dependent compared with phloem-mobile herbicides.     

燕山板栗种质资源AFLP遗传多样性分析

为研究燕山板栗的遗传多样性,用扩增片段长度多态性(amplified fragment length polymorphism,AFLP)技术对44份板栗种质的遗传多样性及遗传距离进行分析,其中36份原产燕山地区的种质中有18份为野生种质和18份为栽培品种,另外8份为原产山东的品种.共检测了384个AFLP位点,有217个是多态性位点,占56.5%,这表明了所检测的板栗材料中存在着明显的遗传多样性.用NT.SYS软件对44份板栗种质进行聚类分析.所有材料聚成4个类群,其中燕山地区原产的板栗材料被聚为3个类群,山东起源的被聚类为1个独立的类群.在所分析的44份材料中,遗传距离在0.0292和0.2214之间.燕山板栗和外来板栗存在着明显的差异,本研究结果与本实验室用RAPD技术分析的结果是一致的.结果对这些板栗材料在育种中的应用具有重要指导意义.     

Microsatellite Marker Based Assessment of Genetic Diversity among Cultivars, Landraces and Wild Relatives in Rice

India being the primary center of origin for rice had a very large treasure of local land races, most of which are out of cultivation today. The exact genetic potential and their differences from commercial varieties and the magnitude of heterogeneity still present in them are not well catalogued. Hence the need to characterize the available land races has become imminent in the modem day concept of crop improvement （Rezai and Frey, 1990）. The present study addresses the utility of SSR markers in divulging the genetic relationships at molecular level among the major component factions office gennplasm viz., local cultivars, land races and wild species collected from a wide range of agro-geographical regions of Indian subcontinent.     

巴音温都尔沙漠典型植物群落土壤物理性质研究

巴音温都尔沙漠是我国北方干旱气候带典型的环境敏感区和生态脆弱区,生态建设和植被恢复对巴音温都尔沙漠生态系统服务功能极为重要.本研究以巴音温都尔沙漠梭梭、唐古特白刺、球果白刺、盐爪爪、膜果麻黄群落土壤为试验对象,对不同植物群落类型土壤物理性状和持水能力进行了研究.结果表明:5种群落中土壤孔隙度、土壤毛管孔隙度与土壤非毛管...     

茄子组织培养再生体系研究初报

以茄子的子叶和下胚轴为外植体,研究了不同激素组合对外植体分化的影响,建立茄子下胚轴高效再生体系,并初步探讨了温度对植株再分化的影响.结果表明:下胚轴不定芽诱导的最适培养基为MS NAA 0.2 mg/L 6-BA 2.5 mg/L,芽诱导率为46%;子叶不定芽诱导的最适培养基为MS NAA 0.2 mg/L KT 2.0 mg/L,芽诱导率为37%.     

结合PCA和GWAS解析甘蓝型油菜株型相关性状的遗传调控位点

作物株型改良是提高收获指数和产量的重要途径,为了解其复杂的遗传调控机制,以373份甘蓝型油菜组成的自然群体为基础,对4个株型相关性状(株高、第一分枝高度、有效分枝数和主花序长度)进行多环境下表型鉴定,组合利用全基因组关联分析(GWAS)和主成分分析(PCA)方法对株型的遗传调控进行解析.研究表明,PCA可以合理地解释株...     

基于卷积神经网络的农作物叶片病害诊断

农作物病害诊断对于及时发现并采取防控措施具有重要意义.本研究针对苹果、玉米、番茄、葡萄等典型农作物的常见叶片病害问题,使用了两种目前使用最广泛的卷积神经网络——VGG 16及Resnet50,对典型农作物叶片病害进行识别.使用AI Challenger比赛的农作物叶片病害数据集图像,并对这些图像进行预处理,构建了47 ...